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Metalworking Occupations
Metalworking is the process of shaping and reshaping metals in order to create useful objects, parts, assemblies, and large scale structures. As a term, it covers a wide and diverse range of processes, skills, and tools for producing objects on every scale: from huge ships, buildings, and bridges, down to precise engine parts and delicate jewellery. The historical roots of metalworking predate recorded history; its use spans cultures, civilizations and millennia. It has evolved from shaping soft, native metals like gold with simple hand tools, through the smelting of ores and hot forging of harder metals like iron, up to and including highly technical modern processes such as machining and welding. It has been used as an industry, a driver of trade, individual hobbies, and in the creation of art; it can be regarded as both a science and a craft. Modern metalworking processes, though diverse and specialized, can be categorized into one of three broad areas known as forming, cutti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dreher An Einer Drehbank
Dreher may refer to: * Dreher (surname) * Dreher Brewery, brewery in Budapest, Hungary * Dreher Township, Wayne County, Pennsylvania, township in Pennsylvania * Bridge in Dreher Township, bridge in Dreher Township, Wayne County, Pennsylvania * Dreher Island State Recreation Area, park in South Carolina * Dreher High School, high school in Columbia, South Carolina * Jacob Wingard Dreher House, historic home in Lexington County, South Carolina * Dreher Shoals Dam, dam in Lexington County, South Carolina See also * Brooklyn (cycling team), a cycling team that used the name Dreher from 1970 to 1972 {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mining
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasibly created Chemical synthesis, artificially in a laboratory or factory. Ores recovered by mining include Metal#Extraction, metals, coal, oil shale, gemstones, limestone, chalk mining, chalk, dimension stone, rock salt, potash, gravel, and clay. The ore must be a rock or mineral that contains valuable constituent, can be extracted or mined and sold for profit. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even fossil water, water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, and final mine reclamation, reclamation or restoration of the land after the mine is closed. Mining ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malleability
Ductility refers to the ability of a material to sustain significant plastic Deformation (engineering), deformation before fracture. Plastic deformation is the permanent distortion of a material under applied stress, as opposed to elastic deformation, which is reversible upon removing the stress. Ductility is a critical mechanical performance indicator, particularly in applications that require materials to bend, stretch, or deform in other ways without breaking. The extent of ductility can be quantitatively assessed using the percent elongation at break, given by the equation: \% \mathrm= \left ( \frac \right )\times100 where l_ is the length of the material after fracture and l_0 is the original length before testing. This formula helps in quantifying how much a material can stretch under tensile stress before failure, providing key insights into its ductile behavior. Ductility is an important consideration in engineering and manufacturing. It defines a material's suitabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anvil
An anvil is a metalworking tool consisting of a large block of metal (usually Forging, forged or Steel casting, cast steel), with a flattened top surface, upon which another object is struck (or "worked"). Anvils are massive because the higher their inertia, the more efficiently they cause the energy of striking tools to be transferred to the work piece. In most cases the anvil is used as a forge, forging tool. Before the advent of modern welding technology, it was the primary tool of metal workers. The great majority of modern anvils are made of cast steel that has been heat treated by either Case-hardening, flame or Induction_hardening, electric induction. Inexpensive anvils have been made of cast iron and low-quality steel, but are considered unsuitable for serious use, as they deform and lack rebound when struck. The largest single piece tool steel anvil that is heat treated is 1600 pounds. This anvil was made in 2023 by Oak Lawn Blacksmith. There are larger anvils tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hammer
A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nail (fastener), nails into wood, to shape metal (as with a forge), or to crush Rock (geology), rock. Hammers are used for a wide range of driving, shaping, breaking and non-destructive striking applications. Traditional disciplines include carpentry, blacksmithing, war hammer, warfare, and mallet percussion, percussive musicianship (as with a gong). Hammering is use of a hammer in its strike capacity, as opposed to pry bar, prying with a secondary claw or grappling with a secondary hook. Carpentry and blacksmithing hammers are generally wielded from a stationary stance against a stationary target as gripped and propelled with one arm, in a lengthy downward plane (geometry), planar arc—downward to add kinetic energy to the impact—pivoting mainly around the shoulder and elbo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock (geology)
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the Earth's crust, crust, and most of its interior, except for the liquid Earth's outer core, outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteor
A meteor, known colloquially as a shooting star, is a glowing streak of a small body (usually meteoroid) going through Earth's atmosphere, after being heated to incandescence by collisions with air molecules in the upper atmosphere, creating a streak of light via its rapid motion and sometimes also by shedding glowing material in its wake. Although a meteor may seem to be a few thousand feet from the Earth, meteors typically occur in the mesosphere at altitudes from . The root word ''meteor'' comes from the Ancient Greek, Greek ''meteōros'', meaning "high in the air". Millions of meteors occur in Earth's atmosphere daily. Most meteoroids that cause meteors are about the size of a grain of sand, i.e. they are usually millimeter-sized or smaller. Meteoroid sizes can be calculated from their mass and density which, in turn, can be estimated from the observed meteor trajectory in the upper atmosphere. Meteors may occur in meteor shower, showers, which arise when Earth passes throu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry
Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during chemical reaction, reactions with other chemical substance, substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both Basic research, basic and Applied science, applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant growth (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Asimov
Isaac Asimov ( ; – April 6, 1992) was an Russian-born American writer and professor of biochemistry at Boston University. During his lifetime, Asimov was considered one of the "Big Three" science fiction writers, along with Robert A. Heinlein and Arthur C. Clarke. A prolific writer, he wrote or edited more than 500 books. He also wrote an estimated 90,000 letters and postcards. Best known for his hard science fiction, Asimov also wrote mystery fiction, mysteries and fantasy, as well as popular science and other non-fiction. Asimov's most famous work is the ''Foundation (book series), Foundation'' series, the first three books of which won the one-time Hugo Award for "Best All-Time Series" in 1966. His other major series are the ''Galactic Empire series, Galactic Empire'' series and the ''Robot series, Robot'' series. The ''Galactic Empire'' novels are set in the much earlier history of the same fictional universe as the ''Foundation'' series. Later, with ''Foundation an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varna Necropolis
The Varna Necropolis (), or Varna Cemetery, is a burial site in the western industrial zone of Varna, Bulgaria, Varna (approximately half a kilometre from Lake Varna and 4 km from the city centre), internationally considered one of the key archaeological sites in world prehistory. The oldest gold treasure and jewelry in the world, dating from 4,600 BC to 4,200 BC, was discovered at the site. Several prehistoric Bulgarian finds are considered no less old – the golden treasures of Hotnitsa, Durankulak (archaeological site), Durankulak, artifacts from the Kurgan settlement of Yunatsite near Pazardzhik, the golden treasure Sakar, as well as beads and gold jewelry found in the Kurgan settlement of Provadia – Solnitsata (“salt pit”). However, Varna gold is most often called the oldest since this treasure is the largest and most diverse. Discovery and excavation The site was accidentally discovered in October 1972 in archaeology, 1972 by excavator operator Raycho Marinov. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
